docs: def execute(self):
          """ print system and cluster info """
          if not self.cmd.is_conn_available():
              return
          if self.cmd.connection.lowest_server_version >= SYSINFO_MIN_VERSION:
              success, rows = self._sys_info()
              self.cmd.exit_code = self.cmd.exit_code or int(not success)
              if success:
                  for result in rows:
                      self.cmd.pprint(result.rows, result.cols)
                  self.cmd.logger.info(
                      "For debugging purposes you can send above listed information to support@crate.io")
          else:
              tmpl = 'Crate {version} does not support the cluster "sysinfo" command'
              self.cmd.logger.warn(tmpl
                                   .format(version=self.cmd.connection.lowest_server_version))